The Gustav Gun: The Biggest Gun Ever Built

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The Gustav Gun was built in 1941 by the Nazis to destroy the Maginot Line. The Maginot Line was notoriously difficult to penetrate, and had stopped the Nazis from advancing into France. Instead of going around the French front littered with machine gun nests, cement bunkers and walls, tanks, soldiers, and barbed wire, the Nazis decided to make a bigger gun to blast through. Because the Gustav gun was so large, and therefore unwieldy, it, fortunately, did not see much use.


Looking at the specs of the Gustav Gun helps to make understanding the epic proportions of the Gustav Gun easier. The Gustav Gun weighed 1,350 tonnes, which complicated the transport of the gun. The Gustav Gun was transported on railroads, which restricted where it could go, but enabled it to move relatively fast. Since the Gustav was so massively heavy, it needed parallel tracks installed. The Gustav had a team of 2500 men installing and removing track as the Gustav traveled. When track couldn’t have been laid, the Gustav had to be disassembled and reassembled, which took about 50 hours with 250 men.

The specially designed Gustav Gun railroad chassis had 40 axles and 80 wheels to support its massive weight and firing force. Not only was the Gustav heavy, it was had a 155 foot chassis, and a 106 foot barrel. The Gustav was 23 feet wide, and 38 feet tall. Since the Gustav could only fire one every 30 to 45 minutes, with a maximum of 14 times per day, it had trouble defending itself. Two flak battalions were employed for air protection, and numerous soldiers to protect from ground attack.

The Gustav shot two types of projectiles, high explosive shot and armor piercing shot, both with an 80 centimeter caliber, and both took 3000 pounds of smokeless gunpowder to fire a round. Each high explosive “bullet” weighed 11,000 pounds, 1,500 pounds of which were actual explosive. This could create a crater 30 feet wide and 30 feet deep, up to 30 miles away.

The armor piercing bullet had a cone tip to travel farther, and go further into objects. Each armor piercing round was 11 feet long, traveled 2,400 feet per second, could travel 24 miles, with the ability to penetrate 250 feet of cement, with 550 pounds of explosive. The armor piercing round was especially suited to penetrate the concrete walls of the French barricade.

A second Gustav was commissioned by the Nazi government, called Dora, named after the chief engineer’s wife of the original Gustav. The Dora was operational by late 1942, but never saw any action and was disassembled before the war was over. The Nazis also planned a tank with a similar 80 centimeter gun, called The Monster. If this tank had been built it would have easily been the largest tank ever built.

The awe of the Gustav’s destruction was never actually experienced by the French for whom it was intended, as it wasn’t completed at the start of the war, when the Blietkrieg rendered French defenses obsolete anyways. It has cemented its place in history as one of the most destructive weapons of all time.